This is from Sybase newsgroups. ASE is Adaptive Server Enterprise:

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Created by Newsgroups
Milan_Mircetic
on 01/18/2001 at 12:42 PM sybase.public.sqlserver.nt

problem with query optimizer

Hi!
We have a version ASE 11.9.2/1031/P/NT(ix86)/03
Our queries become real slow by time even we update statistics every day.
When check plan with showplan we find totaly different showplan for the
query comparing with showplan when query ran well, then we have to add dummy
index to revert to old good showplan and then drop dummy index and after a
month same thing happens again.
Is this Sybase internal bug in this release or what?

Thanks
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Doesn't it sound somewhat familiar? It seems that we aren't alone with a
tricky optimizer. ;-)

C.
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Claudio Valderrama C.
Ingeniero en Informática - Consultor independiente
http://www.cvalde.com